Newer football helmets could cut concussion risk in half, a new study suggests.

Researchers found a 54 percent difference in concussion risk between two different helmets made by the same company in a large study that included data from 1,833 college football players.

The players in the study wore one of two helmet models made by the Riddell company: the older VSR4 and the newer Revolution. All the helmets had been equipped with sensors that recorded forces, or accelerations, experienced by the players' heads each time there was a hit.

"No helmet can completely prevent concussions," said study co-author Stefan Duma, a professor and head of biomedical engineering at Virginia Tech-Wake Forest University. "There's always a risk. All we are saying is that by effectively adding more padding, it reduces the accelerations, and that reduces concussions."

Duma and his colleagues scrutinized concussion and accelerometer data collected from 2005 to 2010 from eight college football teams. All the players wore either the Riddell VSR4 or the Riddell Revolution.

During the years of the study there were a total of 322,725 head impacts in players wearing the VSR4 helmets and 27 concussions, which amounted to 8.37 concussions per 100,000 jolts to the head. Among those wearing the Revolution, there were 958,719 head impacts and 37 concussions, which amounted to 3.86 concussions per 100,000 head impacts.

Concussion experts called the study an important first step, but one that needed to be duplicated, since there is another recently published helmet study that found no difference in concussion protection between older and newer versions.

"The newer helmets are about 40 percent thicker, so it's not a surprise that they would reduce the linear impacts you would record," said Dr. Robert Cantu, a professor of neurology and neurosurgery at the Boston University School of Medicine and co-director of the Center for the Study of Chronic Traumatic Encephalopathy. Cantu also serves on the board of trustees as vice president of the National Operating Committee on Standards for Athletic Equipment.

"What is surprising is the degree to which they appear to have found concussion to be reduced," he added.

Cantu said he was concerned about the small number of concussions that were reported. Numbers were also an issue for David Hovda, a professor of neurosurgery and director of the UCLA Brain Injury Research Center.

There was far less data from the VSR4 wearing players, Hovda pointed out. And if there had been more data, the difference between the two helmets might not have been as sharp. Further, Hovda said, you have to take into account the fact that many, many players weren't — and still aren't — reporting concussions.

Ultimately there will just need to be more studies on the topic, said Dr. Douglas Smith, a professor of neurosurgery and director of the Center for Brain Injury and Repair at the University of Pennsylvania Medical Center.

"I would say this is an important study because it instructs us on how to sharpen our focus for future ones," Smith said.